Tick-Borne Relapsing Fever - Causes, Symptoms, Diagnosis, and Treatment

Introduction

Tick-borne relapsing fever is a bacterial infection spread through tick bites. Multiple tick species can spread tick-borne relapsing fever, and each species has a preferred habitat and host. For example, the Ornithodoros hermsii prefer coniferous forests at high altitudes of 1500 to 8000 feet and feed on tree squirrels and chipmunks.

On the other hand, Ornithodoros parkeri and Ornithodoros turicata are found in lower altitudes and feed on ground squirrels, burrowing owls, and prairie dogs. They are found in discrete areas throughout the world, including the plateau region of Mexico, the mountainous region of North America, Central, and South America, Central Asia, the Mediterranean, and much of Africa.

What Is Tick-Borne Relapsing Fever?

Tick-borne relapsing fever is an infection caused by the Borrelia species of bacteria transmitted through tick bites. It is endemic in many countries, and people contract the disease while sleeping in rustic, rodent-infested cabins in the mountains. The condition appears as recurrent episodes of fever separated by afebrile periods, along with muscle and joint pain, nausea, and headache.

What Causes Tick-Borne Relapsing Fever?

A bacteria, Borrelia species, causes tick-borne relapsing fever. It is spread to humans through the bite of an infected tick. Several species of Borrelia could be associated with tick-borne relapsing fever. The Ornithodoros species of ticks are the vectors of the disease. Different species of Ornithodoros act as vectors for specific bacteria; Borrelia hermsii is transmitted by Ornithodoros hermsii, Borrelia parkeri is transmitted by Ornithodoros parkeri, and Borrelia turicatae is by Ornithodoros turicata ticks.

How Is Tick-Borne Relapsing Fever Spread?

Tick-borne relapsing fever is spread to humans by biting an infected Ornithodoros tick. Unlike hard ticks that search their prey in tall grass, they live in rodent burrows, feeding on the rodent as it sleeps. Humans contract the disease when they sleep in a rodent-infested cabin. The ticks come out at night and feed on the person when they sleep. These bites are brief and painless, and people do not even realize they have been bitten. Each species of Borrelia is associated with a specific species of Ornithodoros, and these prefer different habitats.

• Ornithodoros hermsii is generally found in high-altitude areas of 1500 to 1800 feet and is associated with ground or tree squirrels and chipmunks.

• Ornithodoros parkeri is found in lower altitudes, in caves and burrows of ground squirrels, burrowing owls, and prairie dogs.

• Ornithodoros turicata are found in caves, ground squirrels, prairie dogs, and other cave-dwelling animals in the plains of the southwest.

Ornithodoros ticks can live up to ten to 20 years. Each tick takes many blood meals during each life cycle stage; some may even spread the infection to their offspring. Since these ticks have a long lifespan, once a cabin is tick-infested, it will remain so until steps are taken to remove the rodent nests.

What Are the Signs and Symptoms of Tick-Borne Relapsing Fever?

The most characteristic symptom of tick-borne relapsing fever is a high fever that comes and goes. The symptoms of the illness appear about a week after the bite. The fever often lasts for three to five days, usually followed by an afebrile period of five to seven days, and then it returns. The cycle repeats itself if the infection is left untreated. The temperature may jump at the end of each feverish period; it may reach 107 degrees Fahrenheit for ten to 30 minutes and then suddenly drop with profuse sweating. This may also be accompanied by low blood pressure and chills.

Other symptoms include:

• Muscle pain.

• Joint pain.

• Headache.

• Confusion.

• Stomach pain.

• Chills.

• Cough.

• Diarrhea.

• Rash.

• Neck pain.

• Nausea and vomiting.

How Is Tick-Borne Relapsing Fever Diagnosed?

The healthcare provider will examine the physical symptoms and ask if one has been anywhere ticks tend to live. Then they may advise a blood test to test for the causative bacteria. The scientists will then study the blood smear under a microscope and check for Borrelia bacteria.

How Is a Tick-Borne Relapsing Fever Treated?

Tick-borne relapsing fever is treated with antibiotics to kill the bacteria. The symptoms often subside, and the person feels better within a few days. Tetracycline and Doxycycline are the commonly prescribed antibiotics. However, Erythromycin is recommended for pregnant women and children.

However, in a proportion of people, the symptoms may worsen, with high fever and chills. This is called the Jarisch-Herxheimer reaction. This is believed to result from the toxins the dying bacteria release. Usually, these symptoms subside on their own, but in rare cases, they may cause breathing problems that require medical help.

What Are the Complications of Tick-Borne Relapsing Fever?

Complications from tick-borne relapsing fever are rare, as most people cure with antibiotics. Complications include:

• Liver problems.

• Inflammation of the heart.

• Encephalitis.

• Pneumonia.

• Seizures.

• Bell's palsy.

• Extensive bleeding.

• Coma.

• Death.

• If the mother has had the illness, premature birth, and low birth weight of the baby.

How Can Tick-Borne Relapsing Fever Be Prevented?

• Do not stay or sleep in rodent-infested cabins or buildings. Check for rodent droppings or other evidence of rodents before staying in a new place.

• If renting a new cabin and one notices rodent infestation, notify the owner to alert them.

• If staying in a cabin in a mountainous region, avoid sleeping on a bed that touches the wall or on the floor. Also, change and wash the beddings before use.

• Use insect repellents on the clothes and skin to prevent ticks, specially repellents containing DEET (N, N-diethyl-meta-toluamide) or permethrin.

• Consult a licensed pest control professional to identify and remove rodent nests from the attics, walls, and other crawl spaces, treat the cracks in the wall with pesticides and establish a pest control program to keep rodents away from the house.

• Pesticide control of the building is necessary. Eliminating the rodents without tick control could increase the risk of people contracting the disease because hungry ticks will seek other hosts to feed on if the rodents are unavailable.

Conclusion:

Tick-borne relapsing fever is an illness contracted from tick bites. It is a bacterial infection characterized by recurring fever episodes separated by an afebrile period. The condition is treatable and rarely has any complications. However, consult a doctor if one suspects the disease and take appropriate treatment. Prevent the disease by getting a pest control plan for the building and getting rid of rodent nests.